Connecting Asterisk with VoIP SIP GSM Gateway

By following the setup instructions in this document, Asterisk users will be able to save money on telephony call costs by taking advantage of low mobile-to-mobile call tariffs. The Asterisk IP-PBX configured with the VoIP GSM Gateway HG-1600 will be able to originate calls from Asterisk to the GSM networks, as well as receive calls from GSM to Asterisk – up to 32 simultaneous calls.

Asterisk users benefit from cost-effective fixed to VoIP calls. By connecting Asterisk to the SIP VoIP interface of the VoIP GSM Gateway HG-1600, Asterisk users can save money and benefit from a cost-effective alternative for fixed-to-mobile or mobile-to-fixed telephone calls too. In addition, users can benefit from expanded VoIP connectivity and increased reliability.

Benefits of using Asterisk with HG-4000:

•    g729, g723, g711 codec translation •    Supports GSM, 3G/UMTS and CDMA •    Free CPU resources •    Save g729 licensing costs •    Increased system stability •    On-board codec transcoding •    Larger call volume

The VoIP GSM Gateway HG-1600 is a bi-directional gateway which is designed to transfer calls from VoIP to GSM and vice versa, from GSM to VoIP. It is a scalable VoIP GSM Gateway that can handle from 8 up to 72 GSM – VoIP channels, and is available with Multi-SIM (4 SIM cards per channel), with up to 288 SIM cards.   GSM GATEWAY CONFIGURATION:

VoIP HG-1600 Settings:

Set definitions as follows (or make sure they already exist) Early Media: YesPublic IP: <hg public IP>User Input Indication: RFC2833

ASTERISK INSTALLATION:

Download Asterisk from http://asterisk.org , and follow the instructions to install Asterisk.

ASTERISK CONFIGURATION:

Once the HG-4000 is set, you have to configure Asterisk. On the Asterisk side, you have to setup files as follows:

sip.conf

If using registration:

[hmgw]; GSM VOIP Gateway HG-4000 allow=all dtmfmode=rfc2833 context=from-hmgw

username=hmgwSecret=<secret>host=dynamiccanreinvite=no

Without registration:

[hmgw]; GSM VOIP Gateway HG-4000 allow=all dtmfmode=rfc2833 context=from-hmgw host=<host>canreinvite=noinsecure=very

extensions.conf

; ******* handle GSM calls in asterisk ******* [from-hmgw] exten => _X.,1,answer ;add your code here ; ******* transfer calls to GSM gateway connected through SIP interface ****** [to-hmgw] exten => _X.,1,dial(sip/hmgw/${EXTEN}) exten => _X.,n,hangup